I applied and received a visa approval letter in which my granted arrival date is January 23, 2014. But my plan changed and I need to arrive in Vietnam in January 21. Does this visa approval letter work or must I apply for a new one? Please reply me as soon as possible. Thks

Be kindly informed that you are allowed to enter Vietnam later than the arrival date granted in your visa approval letter, but earlier arrival is not allowed.

In this case, you should apply for a new visa approval letter for your changed plan. You can access here to apply for a new one with Vietnam-visa.co.uk.

Wish you all good things.